Baseline studies of The Clay Minerals Society source clays : Specific surface area by Brunauer Emmett Teller (BET) method - Dogan, A. Umran (University of Iowa. Department of Chemical and Biochemical Engineering) ; Dogan, Meral (Hacettepe University. Department of Geological Engineering) ; Omal, Muserref (Ankara University. Department of Chemistry) ; Sarikaya, Yuksel (Ankara University. Department of Chemistry) ; Aburub, Aktham (Lilly Research Laboratories) ; Wurster, Dale Eric (University of Iowa. Obermann Center for Advanced Studies)